<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>02变量常量</title>
</head>
<body>
<script>
    var a=10;
    var b="你好！";
    var c=true;
    console.log(a,b,c);
    console.log(typeof a,typeof b,typeof c);
    a=3.14;
    console.log(a);
    a=false;
    console.log(a);
    var a='无语了';
    console.log(a);
    let x=1;
    console.log(x,typeof x);
    // let x=true
    // console.log(x,typeof x);
    const y=1;//常量的值不变
    console.log(y,typeof y);
</script>
</body>
</html>